PSB to PSD?

@kv43606971 

Perhaps this script will help:

/*
Batch Save PSB to PSD.jsx
v1.0 - 11th Marsh 2024, Stephen Marsh
https://community.adobe.com/t5/photoshop-ecosystem-discussions/psb-to-psd/m-p/14480985
*/

var originalRulerUnits = preferences.rulerUnits;
preferences.rulerUnits = Units.PIXELS;
var inputFolder = Folder.selectDialog("Please select the input folder:");
var outputFolder = Folder.selectDialog("Please select the output folder:");
var fileList = inputFolder.getFiles(/\.psb$/i);
var fileCounter = 0;

for (var i = 0; i < fileList.length; i++) {

    open(fileList[i]);
    var docName = activeDocument.name.replace(/\.[^\.]+$/, '');
    var savePSDName = File(outputFolder + "/" + docName + ".psd");
    if (app.activeDocument.width.value > 30000 || app.activeDocument.height.value > 30000) {
        fitImage(30000, 30000);
        savePSD(savePSDName);
        activeDocument.close(SaveOptions.DONOTSAVECHANGES);
    } else {
        savePSD(savePSDName);
        activeDocument.close(SaveOptions.DONOTSAVECHANGES);
    }
    fileCounter++;
}

preferences.rulerUnits = originalRulerUnits;
alert('Script completed!' + '\n' + fileCounter + ' files saved to:' + '\r' + outputFolder.fsName);


function fitImage(fWidth, fHeight) {
    /* NEARESTNEIGHBOR | BILINEAR | BICUBIC | BICUBICSMOOTHER | BICUBICSHARPER | BICUBICAUTOMATIC */
    if (activeDocument.height.value > activeDocument.width.value) {
        activeDocument.resizeImage(null, UnitValue(fHeight, "px"), null, ResampleMethod.BICUBIC);
    } else {
        activeDocument.resizeImage(UnitValue(fWidth, "px"), null, null, ResampleMethod.BICUBIC);
    }
}

function savePSD(saveFile) {
    psdSaveOptions = new PhotoshopSaveOptions();
    psdSaveOptions.embedColorProfile = true;
    psdSaveOptions.alphaChannels = true;
    psdSaveOptions.layers = true;
    activeDocument.saveAs(saveFile, psdSaveOptions, true, Extension.LOWERCASE);
}

https://prepression.blogspot.com/2017/11/downloading-and-installing-adobe-scripts.html